Filamentous Fungi With Impaired PTRB Activity For Altered Protein Production

Abstract

A filamentous fungal cell is provided comprising at least one mutation, wherein the filamentous fungal cell has impaired ptrB activity and has altered expression of a protein of interest as compared to a corresponding parent filamentous fungal cell. In one embodiment, the altered expression of the protein of interest is enhanced expression of the protein of interest.

1 . A filamentous fungal cell comprising at least one mutation, wherein the filamentous fungal cell has impaired prtB activity and has altered expression of a protein of interest as compared to a corresponding parent filamentous fungal cell. 
     
     
         2 . The filamentous fungal cell of  claim 1 , wherein the filamentous fungal cell and corresponding parent filamentous fungal cell are protease deficient strains 
     
     
         3 . The filamentous fungal cell of  claim 1 , wherein the mutation is located in a non-coding region adjacent to the ptrB gene locus. 
     
     
         4 . The filamentous fungal cell of  claim 3 , wherein the mutation comprises a deletion in a noncoding region flanking the ptrB gene. 
     
     
         5 . The filamentous fungal cell of  claim 3 , wherein the mutation comprises an insertion mutation. 
     
     
         6 . The filamentous fungal cell of  claim 5 , wherein the insertion mutation comprises insertion of a selectable marker. 
     
     
         7 . The filamentous fungal cell of  claim 1 , wherein the filamentous fungal cell is an  Aspergillus  species, a  Rhizopus  species, a  Trichoderma  species or a  Mucor  species. 
     
     
         8 . The filamentous fungal cell of  claim 1 , wherein the filamentous fungal cell is an  Aspergillus  strain. 
     
     
         9 . The filamentous fungal cell of  claim 7 , wherein the  Aspergillus  species is selected from the group consisting of  A. oryzae, A. niger, A. awamori, A. nidulans, A. sojae, A. japonicus, A. kawachi  and  A. aculeatus . T 
     
     
         10 . The filamentous fungal cell of  claim 7 , wherein the  Trichoderma  species is selected from the group consisting of  Trichoderma  reesei,  Trichoderma  viride,  Trichoderma  koningii, and Trichoderma harzianums. 
     
     
         11 . The filamentous fungal cell of  claim 1 , wherein the altered expression of the protein of interest is enhanced expression of the protein of interest. 
     
     
         12 . The filamentous fungal cell of  claim 10 , wherein the protein of interest is produced in an amount at least about 0% to 200% greater than the production of the same protein in the corresponding parent strain. 
     
     
         13 . The filamentous fungal cell of  claim 11 , wherein the protein of interest is produced in an amount at least about 10% to 60% greater than the production of the same protein in the corresponding parent strain. 
     
     
         14 . The filamentous fungal strain of  claim 1 , further comprising a mutation in, or flanking, a gene encoding a protease. 
     
     
         15 . A filamentous fungal strain capable of expressing a heterologous protein, said strain comprising a mutation that results in decreased ptr2 activity compared to a corresponding parent filamentous fungal strain. 
     
     
         16 . The filamentous fungal strain of  claim 15 , wherein the parent filamentous fungal cell is a protease deficient strain. 
     
     
         17 . A method for increasing expression of a protein of interest in a filamentous fungal host, said method comprising:
 cultivating a mutant of a parent filamentous fungal cell under conditions conducive for production of the protein of interest, wherein the mutant comprises a first nucleic acid sequence encoding the protein of interest and a second nucleic acid sequence comprising a modification of at least one gene locus involved in the production of ptr2; and   isolating the protein of interest.   
     
     
         18 . The method of  claim 17 , wherein the parent filamentous fungal cell is a protease deficient strain.